GM Service Manual Online
For 1990-2009 cars only

Catalytic Converter Replacement 2.2L

Removal Procedure

  1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.

  2. Object Number: 395699  Size: SH
  3. Disconnect the heated oxygen sensor (HO2S) electrical connection.
  4. Remove the catalytic converter to exhaust manifold pipe flange nuts.

  5. Object Number: 42946  Size: SH
  6. Remove the catalytic converter to the muffler flange nuts.
  7. Remove the catalytic converter from the muffler.

  8. Object Number: 42971  Size: SH
  9. Remove the catalytic converter from the catalytic converter hanger.

  10. Object Number: 42989  Size: SH
  11. Remove the catalytic converter from the vehicle.
  12. Remove the heated oxygen sensors (HO2S) as necessary.

Installation Procedure


    Object Number: 42989  Size: SH
  1. Install the heated oxygen sensors (HO2S) as necessary.
  2. Install the catalytic converter and new gasket to the exhaust manifold pipe.

  3. Object Number: 42971  Size: SH
  4. Install catalytic converter to the catalytic converter hanger.

  5. Object Number: 42946  Size: SH
  6. Install the muffler and new gasket to the catalytic converter.
  7. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  8. Install the catalytic converter to the exhaust manifold pipe flange nuts.
  9. Tighten
    Tighten the catalytic converter to the exhaust manifold pipe flange nuts to 35 N·m (26 lb ft).

  10. Install the catalytic converter to the muffler flange nuts.
  11. Tighten
    Tighten the catalytic converter to the muffler flange nuts to 35 N·m (26 lb ft).


    Object Number: 395699  Size: SH
  12. Connect the heated oxygen sensor (HO2S) electrical connection.
  13. Lower the vehicle.

Catalytic Converter Replacement 4.3L RWD

Removal Procedure

  1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.

  2. Object Number: 395704  Size: SH
  3. Disconnect the heated oxygen sensor (HO2S) electrical connection.
  4. Remove the catalytic converter to exhaust manifold pipe flange nuts.

  5. Object Number: 42947  Size: SH
  6. Remove the catalytic converter to the muffler flange nuts.
  7. Remove the catalytic converter from the muffler.

  8. Object Number: 42987  Size: SH
  9. Remove the catalytic converter from the rubber catalytic converter hanger.

  10. Object Number: 42989  Size: SH
  11. Remove the catalytic converter and gasket from the vehicle..
  12. Remove the heated oxygen sensor (HO2S) as necessary.

Installation Procedure


    Object Number: 42989  Size: SH
  1. Install the heated oxygen sensor (HO2S) as necessary.
  2. Install the catalytic converter and new gasket to the exhaust manifold pipe.

  3. Object Number: 42987  Size: SH
  4. Install the catalytic converter to the rubber catalytic converter hanger.

  5. Object Number: 42989  Size: SH
  6. Install the muffler and new gasket to the catalytic converter.
  7. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  8. Install the catalytic converter to the exhaust manifold pipe flange nuts.
  9. Tighten
    Tighten the catalytic converter to the exhaust manifold pipe flange nuts to 35 N·m (26 lb ft).

  10. Install the catalytic converter to the muffler flange nuts.
  11. Tighten
    Tighten the catalytic converter to the muffler flange nuts to 40 N·m (30 lb ft).


    Object Number: 395704  Size: SH
  12. Connect the heated oxygen sensor (HO2S) electrical connection.
  13. Lower the vehicle.

Catalytic Converter Replacement 4.3L 4WD

Removal Procedure

  1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.

  2. Object Number: 395704  Size: SH
  3. Disconnect the heated oxygen sensor (HO2S) electrical connection.
  4. Remove the catalytic converter to exhaust manifold pipe flange nuts.

  5. Object Number: 42948  Size: SH
  6. Remove the catalytic converter to the muffler flange nuts.
  7. Remove the catalytic converter from the muffler.

  8. Object Number: 42974  Size: SH
  9. Remove the catalytic converter from the rubber catalytic converter hangers.

  10. Object Number: 42989  Size: SH
  11. Remove the catalytic converter and gasket from the vehicle.
  12. Remove the heated oxygen sensors (HO2S) as necessary.

Installation Procedure


    Object Number: 42989  Size: SH
  1. Install the heated oxygen sensors (HO2S) as necessary.
  2. Install the catalytic converter and new gasket to the exhaust manifold pipe.

  3. Object Number: 42974  Size: SH
  4. Install the catalytic converter to the catalytic converter rubber hangers.

  5. Object Number: 42948  Size: SH
  6. Install the muffler and new gasket to the catalytic converter.

  7. Object Number: 42989  Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  8. Install the catalytic converter to the exhaust manifold pipe flange nuts.
  9. Tighten
    Tighten the catalytic converter to the exhaust manifold pipe flange nuts to 35 N·m (26 lb ft).

  10. Install the catalytic converter to the muffler flange nuts.
  11. Tighten
    Tighten the catalytic converter pipe to the muffler flange nuts to 40 N·m (30 lb ft).


    Object Number: 395704  Size: SH
  12. Connect the heated oxygen sensor (HO2S) electrical connection.
  13. Lower the vehicle.